Apparatus for cooling electronic circuitry

ABSTRACT

An apparatus cools electronic circuitry. An enclosure surrounds the electronic circuitry and has plural surfaces. Air intake holes are disposed in at least one surface and face at least one first direction. Air exhaust holes are disposed in at least another surface and face at least one second direction different than the first direction. A heat sink is in thermal contact with the circuitry and conducts heat generated by the circuitry. When a fan operates, air is drawn from an exterior of the enclosure through the air intake holes, absorbs heat from the heat sink, and then is directed through the air exhaust holes into the exterior of the enclosure. The heat sink is further in thermal contact with the enclosure so that when the fan does not operate, heat is drawn from the circuitry to the enclosure via the heat sink and is dissipated from the exterior.

CROSS-REFERENCE TO RELATED APPLICATIONS

This application is a continuation-in-part of U.S. patent applicationSer. No. 15/602,334, filed May 23, 2017, the disclosure of which isincorporated herein by reference. The present application further claimsthe benefit of the filing date of U.S. Provisional Patent ApplicationNo. 62/345,169, filed Jun. 3, 2016, the disclosure of which isincorporated herein by reference.

BACKGROUND OF THE INVENTION Technical Field

Aspects of the embodiments relate generally to rack mounted equipmenthousings, and more specifically to systems, methods, and modes forcooling of circuitry located within rack mounted equipment housings thatsubstantially eliminates or prevents problems associated with currentlyavailable technology.

Background Art

As those of skill in the art of the design, manufacture, and sale ofelectronic equipment can no doubt appreciate, fans are sometimesnecessary to cool integrated circuits, such as those use in transmittersand receivers sold in Digital Media (DM) products manufactured byCrestron Electronics, Inc., of Rockleigh, N.J., due to their highthermal dissipation levels. Typically, fans are located either to theside of the high wattage device, or right above the high wattage devicein order to cool the device effectively, or at least to try and cool thedevice effectively. A typical installation places the vent holes in thecontainer housing (housing) right above the fan. This approachintroduces several drawbacks: If the vent holes are blocked duringinstallation, this will result in overheating the equipment. This is alikely scenario when equipment is installed behind the display. Inaddition, placing the fan right behind the vent holes causes highacoustic noise. Further, the fan may be visible from outside of thehousing, detracting from the aesthetic appearance of the device.

Accordingly, a need has arisen for systems, methods, and modes forcooling of circuitry located within rack mounted equipment housings thatsubstantially eliminates or prevents problems associated with currentlyavailable technology.

SUMMARY OF THE INVENTION

This Summary is provided to introduce a selection of concepts in asimplified form that are further described below in the DetailedDescription. This Summary is not intended to identify key features oressential features of the claimed subject matter, nor is it intended tobe used to limit the scope of the claimed subject matter. It is to beunderstood that both the general and detailed descriptions that followare exemplary and explanatory only and are not restrictive.

DISCLOSURE OF INVENTION

In accordance with an aspect, an apparatus for cooling electroniccircuitry comprises an enclosure configured to surround the electroniccircuitry, the enclosure having a plurality of surfaces, wherein aplurality of air intake holes are disposed in at least one of theplurality of surfaces and face at least one first direction, and aplurality of air exhaust holes are disposed in at least another one ofthe plurality of surfaces and face at least one second direction that isa different direction than the first direction; a heat sink configuredto be in thermal contact with the electronic circuitry and conduct heatgenerated by the electronic circuitry; and a fan arranged such that whenthe fan operates, air is drawn from an exterior of the enclosure throughthe plurality of air intake holes, absorbs heat from the heat sink, andthen is directed through the plurality of air exhaust holes into theexterior of the enclosure; the heat sink being further configured to bein thermal contact with the enclosure so that when the fan does notoperate, heat is drawn from the circuitry to the enclosure via the heatsink and is dissipated from the exterior of the enclosure.

According to a further aspect, an apparatus for cooling electroniccircuitry comprises an enclosure configured to surround the electroniccircuitry, the enclosure having a plurality of surfaces, wherein aplurality of air intake holes are disposed in at least one of theplurality of surfaces, and a plurality of air exhaust holes are disposedin at least another one of the plurality of surfaces; an air plenumpiece disposed within the enclosure and configured to divide an interiorregion of the enclosure into a first volume into which the air intakeholes open and a second volume into which the air exhaust holes open,the air plenum piece having an air plenum hole that forms an openingbetween the first volume and the second volume; a fan located in coaxialalignment with the air plenum hole such that when the fan operates, airis drawn from an exterior of the enclosure through the plurality of airintake holes into the first volume, then through the air plenum holeinto the second volume, and thereafter from the second volume throughthe plurality of air exhaust holes into the exterior of the enclosure;and a heat sink configured to be in thermal contact with both theelectronic circuitry and with the enclosure so that when the fan doesnot operate, heat is drawn from the circuitry to the enclosure via theheat sink and is dissipated from the exterior of the enclosure.

According to another aspect, an apparatus for cooling electroniccircuitry comprises an enclosure configured to surround the electroniccircuitry, the enclosure including: a first portion configured tosupport a circuit board having the electronic circuitry and having afirst surface, a second portion having a second surface disposedopposite the first surface, and a plurality of side surfaces disposedbetween the first surface and the second surface, wherein a plurality ofair intake holes are disposed in at least the second surface, and aplurality of air exhaust holes are disposed in at least one of theplurality of side surfaces; an air plenum piece that includes asubstantially planar portion that is disposed between the first andsecond surfaces, the substantially planar portion being configured todivide an interior region of the enclosure into a first volume intowhich the air intake holes open and a second volume into which the airexhaust holes open, and having an air plenum hole that forms an openingbetween the first volume and the second volume; a heat sink having alower portion that is disposed in the second volume between the circuitboard and the air plenum piece, the lower portion having a bottomsurface that is in thermal contact with the circuitry and having a topsurface, and a fan disposed atop the heat sink and in coaxial alignmentwith the air plenum hole such that when the fan operates, cooling air isdrawn from an exterior of the enclosure through the plurality of airintake holes into the first volume, then from the first volume into thesecond volume, and thereafter from the second volume through theplurality of air exhaust holes into the exterior of the enclosure in adirection other than from a direction from which the cooling air isdrawn, the movement of the cooling air in the second volume drawing heataway from the heat sink; the heat sink having at least one verticalportion that extends at one end from the lower portion of the heat sink,and then alongside part a region of the substantially planar portion ofthe air plenum piece, and the heat sink having at least one upperportion disposed at another end of the at least one vertical portion,the at least one upper portion being in thermal contact with theenclosure so that when the fan does not operate, heat is drawn from thecircuitry to the enclosure via the heat sink and is dissipated into theexterior of the enclosure.

BRIEF DESCRIPTION OF DRAWINGS

The accompanying figures further illustrate the present embodiments.

The above and other objects and features of the embodiments will becomeapparent and more readily appreciated from the following description ofthe embodiments with reference to the following figures. Differentaspects of the embodiments are illustrated in reference figures of thedrawings. It is intended that the embodiments and figures disclosedherein are to be considered to be illustrative rather than limiting. Thecomponents in the drawings are not necessarily drawn to scale, emphasisinstead being placed upon clearly illustrating the principles of thepresent embodiments. In the drawings, like reference numerals designatecorresponding parts throughout the several views.

BRIEF DESCRIPTION OF THE SEVERAL VIEWS OF THE DRAWING

FIG. 1 illustrates an exploded perspective view of a housing ofelectronic circuitry in which a cooling apparatus has been implementedaccording to aspects of the embodiments.

FIG. 2A illustrates a sectional view along lines A-A of FIG. 1 of thecooling apparatus according to aspects of the embodiments.

FIG. 2B illustrates a sectional view along lines B-B of FIG. 1 of thecooling apparatus according to aspects of the embodiments.

FIG. 3 illustrates a perspective view of a bottom portion of the coolingapparatus of FIGS. 1 and 2 according to aspects of the embodiments.

FIG. 4 illustrates a perspective view of an electronic printed circuitboard with a cooling fan mounted thereupon according to aspects of theembodiments.

FIG. 5A illustrates a perspective view of an air plenum piece used inthe cooling apparatus of FIGS. 1 and 2 according to aspects of theembodiments.

FIG. 5B illustrates a side view of the air plenum piece used in thecooling apparatus of FIGS. 1 and 2 according to aspects of theembodiments.

FIG. 6 illustrates a perspective view of an upper portion of the coolingapparatus of FIGS. 1 and 2 according to aspects of the embodiments.

FIG. 7 illustrates an exploded perspective view of a housing ofelectronic circuitry in which a cooling apparatus has been implementedaccording to aspects of other embodiments.

FIG. 8 illustrates a perspective view of a bottom portion of the coolingapparatus of FIG. 7.

FIG. 9 illustrates a perspective view of an electronic printed circuitboard disposed within the cooling apparatus of FIG. 7.

FIG. 10 illustrates a perspective view of a heat sink and cooling fan ofthe cooling apparatus of FIG. 7.

FIG. 11 illustrates a perspective view of an air plenum piece of thecooling apparatus of FIG. 7.

FIG. 12 illustrates a perspective view of an upper portion of thecooling apparatus of FIG. 7.

DETAILED DESCRIPTION OF THE INVENTION

The embodiments are described more fully hereinafter with reference tothe accompanying drawings, in which aspects of the embodiments areshown. In the drawings, the size and relative sizes of layers andregions may be exaggerated for clarity. Like numbers refer to likeelements throughout. The embodiments may, however, be embodied in manydifferent forms and should not be construed as limited to the aspects ofthe embodiments set forth herein. Rather, these embodiments are providedso that this disclosure will be thorough and complete, and will fullyconvey the scope of the aspects of the embodiments to those skilled inthe art. The scope of the embodiments is therefore defined by theappended claims. The detailed description that follows is written fromthe point of view of a control systems company, so it is to beunderstood that generally the concepts discussed herein are applicableto various subsystems and not limited to only a particular controlleddevice or class of devices, such as audio electronic devices.

Reference throughout the specification to “one embodiment” or “anembodiment” means that a particular feature, structure, orcharacteristic described in connection with an embodiment is included inat least one embodiment of the embodiments. Thus, the appearance of thephrases “in one embodiment” on “in an embodiment” in various placesthroughout the specification is not necessarily referring to the sameembodiment. Further, the particular feature, structures, orcharacteristics may be combined in any suitable manner in one or moreembodiments.

Unless the context clearly requires otherwise, throughout thedescription and the claims, the words ‘comprise’, ‘comprising’, and thelike are to be construed in an inclusive sense as opposed to anexclusive or exhaustive sense; that is to say, in the sense of“including, but not limited to”.

LIST OF REFERENCE NUMBERS FOR THE MAJOR ELEMENTS IN THE DRAWING

The following is a list of the major elements in the drawings innumerical order.

-   100 Electronic Circuity Cooling Apparatus (Cooling Apparatus)-   102 Lower Portion-   104 Circuit Board with Cooling Fan (Circuit Board)-   106 Air Plenum Piece (APP)-   108 Upper Portion-   202 Cooler Intake Air-   204 Warmer Output Air-   302 Rear Air Inlet-   304 Rear Panel-   306 Bottom Panel-   402 Fan-   404 Heat Sink-   406 Circuitry-   502 Air Plenum Hole (Hole)-   504 Horizontal Surface-   506 Vertical Wall-   508 Plenum Planar Portion-   510 Plenum Air Channel-   512 Assembly Holes-   602 Top Air Inlet-   604 Front Air Inlet-   606 Side Air Exhaust-   608 Assembly Screws-   610 Front Panel-   612 Left Side Panel-   614 Right Side Panel-   616 Upper Panel-   700 Electronic Circuity Cooling Apparatus (Cooling Apparatus)-   702 Lower Portion-   704 Circuit Board-   706 Heat Sink with Cooling Fan (Heat Sink)-   708 Air Plenum Piece (APP)-   710 Upper Portion-   802 Rear Air Inlet-   804 Rear Panel-   806 Bottom Panel-   902 Circuit Board Surface-   904 Circuitry-   906 Heat Sink Footprint-   1002 Fan-   1004 Lower Horizontal Portion-   1006 Vertical Wall-   1008 Upper Horizontal Portion-   1010 Pin Array-   1102 Air Plenum Hole (Hole)-   1106 Vertical Wall-   1108 Plenum Planar Portion-   1110 Plenum Air Channel-   1202 Top Air Inlet-   1204 Front Air Inlet-   1206 Side Air Exhaust-   1208 Assembly Screws-   1210 Front Panel-   1212 Left Side Panel-   1214 Right Side Panel-   1216 Upper Panel

LIST OF ACRONYMS USED IN THE SPECIFICATION IN ALPHABETICAL ORDER

The following is a list of the acronyms used in the specification inalphabetical order.

APP Air Plenum Piece

MODE(S) FOR CARRYING OUT THE INVENTION

The different aspects of the embodiments described herein pertain to thecontext of a cooling system for audio electronics, but is not limitedthereto, except as may be set forth expressly in the appended claims.

For 40 years Creston Electronics Inc., has been the world's leadingmanufacturer of advanced control and automation systems, innovatingtechnology to simplify and enhance modern lifestyles and businesses.Crestron designs, manufactures, and offers for sale integrated solutionsto control audio, video, computer, and environmental systems. Inaddition, the devices and systems offered by Crestron streamlinestechnology, improving the quality of life in commercial buildings,universities, hotels, hospitals, and homes, among other locations.Accordingly, the systems, methods, and modes of the aspects of theembodiments described herein, as embodied as digital media products suchas DM-TX-4K-1000-SFP (4K transmitter) and DM-RX-4K-1000-SFP (4Kreceiver), can be manufactured by Crestron Electronics Inc., located inRockleigh, N.J., and have been marketed and sold under the registeredtrademark name of “DigitalMedia.”

FIG. 1 illustrates an exploded perspective view of a housing ofelectronic circuitry in which a cooling apparatus has been implementedaccording to aspects of the embodiments. According to aspects of theembodiments, components of cooling apparatus 100 include both extraneouscomponents, and the manner in which they have been implemented indesign, but also intrinsic components, such as components of the housingassembly itself. This combination of devices will be described ingreater detail below.

Electronic circuitry cooling apparatus (cooling apparatus) 100 compriseslower portion 102, circuit board with cooling fan (circuit board) 104,air plenum piece (APP) 106, and upper portion 108.

As shown in FIG. 3, which illustrates a perspective view of bottomportion 102 of cooling apparatus 100, lower portion 102 comprises rearair inlet 302, which is located on rear panel 304, and further comprisesbottom panel 306 according to aspects of the embodiments.

Shown in FIG. 4 is circuit board 104, which itself comprises cooling fan402 located on top of heat sink 404 and circuitry 406, which isconfigured and arranged in a manner well known to those of skill in theart, and thus, in fulfillment of the dual purposes of clarity andbrevity, a detailed discussion thereof has been omitted from herein.

FIG. 5A illustrates air plenum piece 106, which comprises plenum planarportion 508, vertical tabs 506 a,b, horizontal tabs 504 a,b, and airplenum hole 502, located on plenum planar portion 508. In addition, airplenum piece 106 further comprises a plurality of mounting holes 512.air plenum piece 106 is adapted and shaped in the form of an elongatedchannel, and as such comprises channel 510 that includes a channel widthand a channel length according to aspects of the embodiments.

FIG. 6 illustrates upper portion 108, which comprises front panel 610,left side panel 612, right side panel 614, and upper panel 616. Inaddition, front panel 610 comprises front air inlets 604, left sidepanel 612 comprises side air exhaust 606 a, and right side panel 614comprises side air exhaust 606 b according to aspects of theembodiments. Further, top portion 616 comprises top air inlet 602according to aspects of the embodiments.

Described in several of the drawings are the nomenclatures that indicaterelative position of “front,” “rear,” “side,” “top,” “bottom,” and othersuch similar indicators of relative position. As those of skill in theart can appreciate, such indicators are not to be taken in a limitingsense, and are merely provided to make the discussion and description ofthe aspects of the embodiments spatially easier to understand, and toplace pieces or components thereof in spatial or relative context witheach other.

Attention is now directed to FIGS. 1, 2A, 2B, 5A, 5B, and 6. Accordingto aspects of the embodiments, cooler intake air (intake air) 202 isdrawn in from top air inlet 602, front air inlet 604, and rear air inlet302 by operation of fan 402. As intake air 202 is drawn in, it is forcedto travel on top of air plenum piece 106, because, as shown in FIGS. 1,2A, 2B, and 5A, air plenum piece 106 has been designed and fabricated tosubstantially enclose the air intakes, separate them from the lowerportion of the housing enclosure, and provide only one path for intakeair 202 to travel as it is pulled in by fan 402; that is, air plenumpiece 106 substantially seals the upper portion of the interior of thehousing from the lower portion (anything below air plenum piece 106),which includes circuit board 104 and the upper surface of lower portion102. Further, since all air intake holes (302, 602, 604) are located inthat space that is defined by the upper level of air plenum piece 106and the interior lower surface of upper portion 108, intake air 202travels through channel 510 to hole 502 and fan 402, via operation offan 402.

Intake air 202 is pulled through rear air inlet 302, top air inlet 602,and front air inlet 604, and then through hole 502 by fan 402, whereinit passes over and through heat sink 404 and circuitry 406 located oncircuit board 104. As the air is expelled from fan 402 and passes overheat sink 404 and circuitry 406, it picks up heat, and becomes ortransitions to warmer output air (output air) 204. Output air 204 isforced to be expelled through side air exhausts 606 a,b according toaspects of the embodiments, as they are the only exhausts available forthe warmer air to travel according to aspects of the embodiments.

According to aspects of the embodiments, air duct conduit system(cooling apparatus) 100 has been created such that air can be ducted tofan 402 from multiple air inlets 302, 602, 604. Air exhaust vents 606a,b are located on the left and right side walls 612, 614, respectively.Having a plurality of surfaces with inlets 302, 602, 604 substantiallyprevents the possibility of over-heating due to blocked air inletsaccording to aspects of the embodiments. Air plenum piece 106 contains asuitably sized hole 502 that is about the size of the diameter of thefan blades, and is spaced in close proximity to the fan blades. Inaddition, air plenum piece 106 is sized and located such that it leavesa very small gap between air plenum piece 106 and the front and rearwalls, so that air is drawn from the top surface 616, and front and rearwalls 610, 304 according to aspects of the embodiments. According tofurther aspects of the embodiments, air plenum piece 106 of thisconfiguration also reduces the amount of fan noise radiated from thecontainer because the fan is located farther away from the exteriorsurface, and the intake air has a longer distance to travel prior toencountering the blades of fan 402; as those of skill in the art canappreciate, air intakes that are located relatively closer to the bladesof a fan create more noise than when air intakes are located relativelyfarther away from the blades of the fan. Further, cooler intake air 202is pulled in from multiple and larger 602, 604, 302 surfaces thatfurther reduces the acoustic noise generated by the fan as those skilledin the art can appreciate. According to still further aspects of theembodiments, locating fan 402 farther away from inlets 302, 602, 604lowers the pressure drop through the same inlets 302, 602, 604, whichcan be increased to accommodate greater cooling capacity; thus, moreheat can be removed with a smaller fan than would otherwise be the case.

Attention is again directed to FIG. 5A, which illustrates a perspectiveview of air plenum piece 106 used in cooling apparatus 100 of FIGS. 1and 2 according to aspects of the embodiments, and FIG. 5B, whichillustrates a side view of air plenum piece 106 used in the coolingapparatus of FIGS. 1 and 2 according to aspects of the embodiments. Asshown in FIGS. 5A and 5B, air plenum piece 106 comprises a substantiallyplanar portion (plenum planar portion) 508, within which is located hole502. Hole 502 is sized to be substantially similar in diameter to thediameter of the blades of fan 402, which, according to aspects of theembodiments, is located substantially coaxially in alignment with hole502 (e.g., an imaginary line drawn through the center of hole 502 andthe center of the fan blades would be substantially parallel andco-located in space and perpendicular to fan 402 and hole 502). On bothsides of plenum planar portion 508 are located respective substantiallyvertical walls (walls) 506 a,b, which form plenum air channel 510.

Plenum air channel 510 is the three dimensional space through whichintake air 202 travels to get to hole 502 and fan 402. Plenum airchannel 510 is formed not only by walls 506 a,b, but also by rear panel304 (FIG. 3; of lower portion 102) and front panel 610 (FIG. 6; of upperportion 108), according to aspects of the embodiments. According toaspects of the embodiments, it is the creation of plenum air channel 510that causes the cool intake air 202 to be drawn into hole 502 by fan402. As shown in FIGS. 5A and 5B, channel 510 has a length and width;due to the design and fabrication thereof, the channel length isapproximately the interior linear distance from front panel 610 to rearpanel 304 according to aspects of the embodiments. The channel width isthe linear distance between first vertical wall 506 a and secondvertical wall 506 b, as shown in FIG. 5B, according to aspects of theembodiments. The volume of channel 510 is defined by the product of thechannel length, channel width, and channel depth (which is the height ofvertical walls 506 a,b), and has been sized to accommodate the amount ofair that can be drawn in by fan 402 and required to maintain an adequaterate of cooling (or rate of heat dissipation) of the electroniccircuitry located on circuit board 104.

FIG. 6 illustrates a perspective view of upper portion 108 of coolingapparatus 100 of FIGS. 1 and 2 according to aspects of the embodiments.As shown in FIG. 6, upper portion 108 comprises all but one of thesections of air intake and air exhaust holes. Upper portion 108comprises top air inlet 602 (located on upper panel 616), front airinlet 604 (located on front panel 610), side air exhaust 606 a (locatedon left side panel 612), and side air exhaust 606 b (located on rightside panel 614). While rear air inlet 302 is shown as being located onlower portion 102, those of skill in the art can appreciate that upperportion 108 could have been fabricated to encompass all four panels orwalls, or the walls/ could have been separately fabricated, among otherpossible combinations of assembly. According to still further aspects ofthe embodiments, air plenum piece 106 need not have oriented in themanner shown, but could also have had channel 510 cross in a directionperpendicular to that as shown; e.g., channel 510 could have run betweenleft side panel 612 and right side panel 614, as opposed to runningbetween front panel 610 and rear panel 304.

According to further aspects of the embodiments, the relative positionand location of the air inlets as not being on a same surface of the airexhausts means that little or no hot exhaust air can be vacuumed intothe air inlets; because of this configuration, only ambient air, or atleast not hot air from the same enclosure will be pulled in by fan 402through air inlets so that the cooling benefit of the moving air will bemaximized. According to still further aspects of the embodiments, therelatively far distance between the blades of fan 402 and the air inletsmeans that the acoustical noise generated by the fan will besubstantially minimized, and the cooling effectiveness substantiallymaximized. According to aspects of the embodiments, the height ordistance of air plenum piece 106 above fan 402 can be about equal to thediameter of the blades of fan 402 in order to substantially minimizeacoustical noise generated by fan 402.

According to additional aspects of the embodiments, the acoustical noisegenerated by the fan can be further decreased by reducing the rotationalspeed (number of RPM) of the fan when maximum cooling is not needed butsome cooling is still required. As an example, when power to thecircuitry is shut off or reduced after normal operation of thecircuitry, the circuitry may still require some cooling, though notrequiring the same air flow as needed during normal operation. Bycontinuing to operate the fan at a reduced number of RPM, cooling of thecircuitry continues for a time and quieter operation is attained.

According to aspects of other embodiments, in place of operating the fanat a reduced RPM, the circuitry is cooled by providing a configurationin which the heat sink is shaped to provide a passive heat conductionpath from the circuitry to one or more surfaces of the housing, wherethe heat dissipates, for example, to the surrounding air. By providingthis additional heat conduction path, heat continues to be drawn fromthe circuitry even after power to the circuitry is reduced or removed,so that the fan may be completely shut down at this time. As a result,fan noise after power down or power reduction is eliminated.

FIG. 7 illustrates an exploded perspective view of a housing ofelectronic circuitry in which a cooling apparatus has been implementedaccording to aspects of the other embodiments. Electronic circuitrycooling apparatus (cooling apparatus) 700 includes a lower portion 702,a circuit board 704, a heat sink with cooling fan (heat sink) 706, anair plenum piece (APP) 708, and an upper portion 710.

Referring now to FIG. 8, a perspective view of the lower portion 702 ofthe cooling apparatus 700 is shown. The lower portion 702 includes arear air inlet 802, which is located on a rear panel 804, and a bottompanel 806. The structure and function of the lower portion 702 issimilar to that of the lower portion 302 shown in FIGS. 1-3.

FIG. 9 shows a perspective view of the circuit board 704. The circuitboard is typically supported by the lower portion 702. The circuit boardincludes a circuit board panel 902 upon which are mounted variouscircuitry 904. Some or all of the circuitry 904, or at least thoseelements that require cooling, are mounted within a “footprint” of wherethe heat sink 706 will overlie, depicted in this example by the regionenclosed by dashed line 906. The heat sink 706 will be in thermalcontact with the circuitry within this region.

FIG. 10 depicts a perspective view of the heat sink 706. The heat sinkincludes a lower horizontal portion 1004 that is disposed atop thecircuitry 904. A bottom surface of the lower horizontal portion 1004 isin thermal contact with the circuitry 904 and is configured to draw heataway from the circuitry. An array of pins 1010 is disposed on anopposing surface of the lower horizontal portion 1004 and conducts heataway from the circuitry 904 and from the lower horizontal surface 1004.A cooling fan 1002 is located atop of heat sink 706 and, when operating,draws air over the array of pins 1010 to transfer heat to air circulatedby the fan.

The heat sink 706 also includes vertical walls 1006 which are located,for example, at each end of the lower horizontal portion 1004 and whichextend at one end from the lower horizontal portion 1004. At an opposingend of each vertical wall 1006 is disposed a raised horizontal portion1008. The vertical walls 1006 and the raised horizontal portions 1008provide an alternative path for conducting heat away from the circuity904. That is, when the cooling apparatus 700 is assembled, the raisedhorizontal portions 1008 are in thermal contact with the upper portion710 and allow heat from the circuitry, for example, to radiate andconvect into the surrounding air or to an external heat sink. Thus, whenthe cooling fan 1002 is not in operation, cooling for the circuity 904is still provided.

FIG. 11 provides a perspective view of the air plenum piece 708. The airplenum piece includes a plenum planar portion 1108, vertical tabs 1106,and an air plenum hole 1102 located on plenum planar portion 1108. Theair plenum piece 708 is configured to form a channel 1110 and direct theflow of air in a manner similar to that described regarding the airplenum piece 106.

The plenum planar portion 1108 of the air plenum piece 708, however, hasa narrower width in the region that overlies the heat sink 706 to permitthe vertical walls 1006 of the heat sink 706 to extend upward above theair plenum piece 708 and allow the raised horizontal portions 1008 ofthe heat sink 706 to contact the upper housing when the coolingapparatus 700 is assembled. The vertical walls 1006 of the heat sink 706are also configured to fit tightly against the edges of the planarportion 1108 and serve in place of the vertical tabs 1106 in that regionof the air plenum piece 708. Thus, the combination of the vertical tabs1106 and the vertical walls 1006 of the heat sink 706 substantiallyprovide a single path for the intake air pulled in by fan 1002.

FIG. 12 depicts a perspective view of the upper portion 710 of thecooling apparatus 700. The upper portion includes a front panel 1210, aleft side panel 1212, a right side panel 1214, and an upper panel 1216.The front panel 1210 includes a plurality of front air inlets 1204. Theleft side panel 1212 includes left side air exhaust openings 1206 a, andthe right side panel 1214 includes right side air exhaust openings 1206b. Further, the top portion 1216 includes a plurality of top air inletopenings 1202. The structure of the upper portion 710 is similar to thatof the upper portion 108 shown in FIGS. 1-2 and 6.

According to aspects of the embodiments, when the fan 1002 operates, thecircuitry is cooled by the cooling apparatus 700 in a manner similar tothat carried out by the cooling apparatus 100. Namely, cooling intakeair is drawn in through the top air inlet 1202, the front air inlet1204, and the rear air inlet 802 by the fan 1002. As the intake air isdrawn in, the intake air is directed along the top surface of the airplenum piece 708 and provides a single path for the intake air pulled inby fan 1002. That is, the air plenum piece 708, together with thevertical walls 1006 of the heat sink 706, substantially seals the upperportion of the interior of the housing from the lower portion (thevolume below the air plenum piece 708), which includes the circuit board704 and the upper surface of the lower portion 702. Further, since allof the air intake openings (802, 1202, 1204) are located in the spacedefined by the upper level of the air plenum piece 708 and the interiorlower surface of upper portion 710, the intake air travels through theair channel 1110 to the hole 1102 via operation of the fan 1002.

The air drawn through the hole 1102 by the fan 1002 then passes over thepin array 1010 of the heat sink 706 and removes heat from the heat sink706 and from the circuitry 904 located on the circuit board 704 that isin thermal contact with the lower horizontal portion 1004 of the heatsink. The warmed output air (output air) is then expelled through sideair exhausts 1206 a, 1206 b.

Alternatively, according to aspects of the embodiments, when the fan1002 does not operate, the cooling apparatus 700 is still able to removeheat from the circuitry because of the configuration of the heat sink706 and the air plenum piece 708. Namely, the vertical walls 1006 of theheat sink 706, which extend upward from the lower horizontal portion1004 of the heat sink and past the narrower region of the air plenumpiece 708, and the upper horizontal portions 1008 of the heat sink,which contact the upper panel 1216 of the upper portion 710, provide analternative path for heat conduction. The vertical walls 1006 and theupper horizontal portions 1008 of the heat sink 706 conduct heat awayfrom the circuitry to the upper panel 1216 of the upper portion 710where the heat circulates to the air that is external to the upper panel1216.

Therefore, according to aspects of the embodiments, during full poweroperation of the circuitry, cooling of the circuitry is provided byoperation of the fan 1004 to draw air through the housing in the mannerdescribed above. Thereafter, when power to the circuitry is removed orreduced, the fan 1004 is shut off and the cooling apparatus 700continues to cool the circuitry by the heat sink 706 conducting heat tothe upper panel 1216. As a result, heat is still removed from thecircuitry without the generation of sound caused by operation of the fan1004.

As discussed in regard to one or more of the Figures described herein,reference is made to several dimensions, including several radii,angles, height, among others. Those of skill in the art can appreciatethat although examples of dimensions are provided, these should not betaken in a limiting manner; that is, the aspects of the embodiments arenot to be construed as defined or limited by the specific example of thedimensions shown and discussed, but instead are provided merely forillustrating an example of what a device that incorporates the aspectsof the embodiments could, in a non-limiting manner, look like.Furthermore, as those of skill in the art can appreciate, since theaspects of the embodiments are directed towards a physical object, withdimensional characteristics, all of the parts will have variousdimensions, some of which are not shown in fulfillment of the dualpurposes of clarity and brevity. According to still further aspects ofthe embodiments, some of these objects will have dimensionalcharacteristics that lend themselves to aesthetic aspects; infulfillment of the dual purposes of clarity and brevity, dimensions inthis regard have also been omitted. Therefore, as the aspects of theembodiments are directed towards a cooling apparatus for use withcooling electronic circuitry, it is to be understood that the dimensionsof the different objects, some dimensions shown, some dimensions notshown, will be understood by those of skill in the art.

The disclosed embodiments provide systems, methods, and modes forcooling of circuitry located within rack mounted equipment housings. Itshould be understood that this description is not intended to limit theembodiments. On the contrary, the embodiments are intended to coveralternatives, modifications, and equivalents, which are included in thespirit and scope of the embodiments as defined by the appended claims.Further, in the detailed description of the embodiments, numerousspecific details are set forth to provide a comprehensive understandingof the claimed embodiments. However, one skilled in the art wouldunderstand that various embodiments may be practiced without suchspecific details.

Although the features and elements of aspects of the embodiments aredescribed being in particular combinations, each feature or element canbe used alone, without the other features and elements of theembodiments, or in various combinations with or without other featuresand elements disclosed herein.

This written description uses examples of the subject matter disclosedto enable any person skilled in the art to practice the same, includingmaking and using any devices or systems and performing any incorporatedmethods. The patentable scope of the subject matter is defined by theclaims, and may include other examples that occur to those skilled inthe art. Such other examples are intended to be within the scope of theclaims.

The above-described embodiments are intended to be illustrative in allrespects, rather than restrictive, of the embodiments. Thus theembodiments are capable of many variations in detailed implementationthat can be derived from the description contained herein by a personskilled in the art. No element, act, or instruction used in thedescription of the present application should be construed as criticalor essential to the embodiments unless explicitly described as such.Also, as used herein, the article “a” is intended to include one or moreitems.

All United States patents and applications, foreign patents, andpublications discussed above are hereby incorporated herein by referencein their entireties.

INDUSTRIAL APPLICABILITY

To solve the aforementioned problems, the aspects of the embodiments aredirected towards systems, methods, and modes for cooling of circuitrylocated within rack mounted equipment housings that substantiallyeliminates or prevents problems associated with currently availabletechnology.

ALTERNATE EMBODIMENTS

Alternate embodiments may be devised without departing from the spiritor the scope of the embodiments.

What is claimed is:
 1. An apparatus for cooling electronic circuitry,the apparatus comprising an enclosure configured to surround theelectronic circuitry, the enclosure having a plurality of surfaces,wherein a plurality of air intake holes are disposed in at least one ofthe plurality of surfaces and face at least one first direction, and aplurality of air exhaust holes are disposed in at least another one ofthe plurality of surfaces and face at least one second direction that isa different direction than the at least one first direction; a heat sinkconfigured to be in thermal contact with the electronic circuitry andconduct heat generated b the electronic circuitry; a fan arranged suchthat when the fan operates, air is drawn from an exterior of theenclosure through the plurality of air intake holes, absorbs heat fromthe heat sink, and then is directed through the plurality of air exhaustholes into the exterior of the enclosure; the heat sink being furtherconfigured to be in thermal contact with the enclosure so that when thefan does not operate, heat is drawn from the electronic circuitry to theenclosure via the heat sink and is dissipated from the exterior of theenclosure; and an air plenum piece that includes a substantially planarportion, the substantially planar portion being configured to divide aninterior region of the enclosure into a first volume into which theplurality of air intake holes open and a second volume into which theplurality of air exhaust holes open, and having an air plenum hole thatforms an opening between the first volume and the second volume; whereinthe heat sink comprises a lower portion that is disposed in the secondvolume, the lower portion having a bottom surface that is in thermalcontact with the electronic circuitry, at least one vertical portionthat extends at one end from the lower portion of the heat sink, andthen alongside part of an edge of the substantially planar portion ofthe air plenum piece, and at least one upper portion disposed at anotherend of the at least one vertical portion, the at least one upper portionbeing in thermal contact with the enclosure so that when the fan doesnot operate, heat is drawn from the electronic circuitry to theenclosure via the heat sink and is dissipated into the exterior of theenclosure; and wherein the substantially planar portion of the airplenum piece further comprises a region having a smaller width than atleast another region of the substantially planar portion, the at leastone vertical portion of the heat sink extends alongside the regionhaving the smaller width.
 2. An apparatus for cooling electroniccircuitry, the apparatus comprising: an enclosure configured to surroundthe electronic circuitry, the enclosure having a plurality of surfaces,wherein a plurality of air intake holes are disposed in at least one ofthe plurality of surfaces and face at least one first direction, and aplurality of air exhaust holes are disposed in at least another one ofthe plurality of surfaces and face at least one second direction that isa different direction than the at least one first direction; a heat sinkconfigured to be in thermal contact with the electronic circuit andconduct heat generated by the electronic circuitry; a fan arranged suchthat when the fan operates, air is drawn from an exterior of theenclosure through the plurality of air intake holes, absorbs heat fromthe heat sink, and then is directed through the plurality of air exhaustholes into the exterior of the enclosure; the heat sink being furtherconfigured to be in thermal contact with the enclosure so that when thefan does not operate, heat is drawn from the electronic circuitry to theenclosure via the heat sink and is dissipated from the exterior of theenclosure; and an air plenum piece that includes a substantially planarportion, the substantially planar portion being configured to divide aninterior region of the enclosure into a first volume into which theplurality of air intake holes open and a second volume into which theplurality of air exhaust holes open, and having an air plenum hole thatforms an opening between the first volume and the second volume; whereinthe heat sink comprises a lower portion that is disposed in the secondvolume, the lower portion having a bottom surface that is in thermalcontact with the electronic circuitry, a first vertical portion thatextends at one end from an edge of the lower portion of the heat sink,and then alongside part of an edge of the substantially planar portionof the air plenum piece, a first upper portion disposed at another endof the first vertical portion, a second vertical portion that extends atone end from an opposing edge of the lower portion of the heat sink, andthen alongside part of an opposing edge of the substantially planarportion of the air plenum piece, and a second upper portion disposed atanother end of the second vertical portion, the first upper portion andthe second upper portion are each in thermal contact with the enclosureso that when the fan does not operate, heat is drawn from the electroniccircuitry to the enclosure via the heat sink and is dissipated into theexterior of the enclosure; and wherein the substantially planar portionof the air plenum piece further comprises a region having a smallerwidth than at least another region of the substantially planar portion,the first vertical portion of the heat sink extends alongside an edge ofthe region having the smaller width, the second vertical portion of theheat sink extends alongside an opposing edge of the region having thesmaller width.
 3. An apparatus for cooling electronic circuitry, theapparatus comprising: an enclosure configured to surround the electroniccircuitry, the enclosure having a plurality of surfaces, wherein aplurality of air intake holes are disposed in at least one of theplurality of surfaces, and a plurality of air exhaust holes are disposedin at least another one of the plurality of surfaces; an air plenumpiece disposed within the enclosure and configured to divide an interiorregion of the enclosure into a first volume into which the plurality ofair intake holes open and a second volume into which the plurality ofair exhaust holes open, the air plenum piece having an air plenum holethat forms an opening between the first volume and the second volume; afan located in coaxial alignment with the air plenum hole such that whenthe fan operates, air is drawn from an exterior of the enclosure throughthe plurality of air intake holes into the first volume, then throughthe air plenum hole into the second volume and thereafter from thesecond volume through the plurality of air exhaust holes into theexterior of the enclosure; and a heat sink configured to be in thermalcontact with both the electronic circuitry and with the enclosure sothat when the fan does not operate, heat is drawn from the electroniccircuitry to the enclosure via the heat sink and is dissipated from theexterior of the enclosure, wherein the heat sink comprises a lowerportion that is disposed in the second volume, the lower portion havinga bottom surface that is in thermal contact with the electroniccircuitry, at least one vertical portion that extends at one end fromthe lower portion of the heat sink, and then alongside part of an edgeof the substantially planar portion of the air plenum piece, and atleast one upper portion disposed at another end of the at least onevertical portion, the at least one upper portion being in thermalcontact with the enclosure so that when the fan does not operate, heatis drawn from the electronic circuitry to the enclosure via the heatsink and is dissipated into the exterior of the enclosure, wherein thesubstantially planar portion of the air plenum piece further comprises acentral region having a smaller width than end regions of thesubstantially planar portion, the at least one vertical portion of theheat sink extends alongside the central region.
 4. An apparatus forcooling electronic circuitry, the apparatus comprising: an enclosureconfigured to surround the electronic circuitry, the enclosure having aplurality of surfaces, wherein a plurality of air intake holes aredisposed in at least one of the plurality of surfaces, and a pluralityof air exhaust holes are disposed in at least another one of theplurality of surfaces; an air plenum piece disposed within the enclosureand configured to divide an interior region of the enclosure into afirst volume into which the plurality of air intake holes open and asecond volume into which the plurality of air exhaust holes open, theair plenum piece having an air plenum hole that forms an opening betweenthe first volume and the second volume; a fan located in coaxialalignment with the air plenum hole such that when the fan operates, airis drawn from an exterior of the enclosure through the plurality of airintake holes into the first volume, then through the air plenum holeinto the second volume and thereafter from the second volume through theplurality of air exhaust holes into the exterior of the enclosure; and aheat sink configured to be in thermal contact with both the electroniccircuitry and with the enclosure so that when the fan does not operate,heat is drawn from the electronic circuitry to the enclosure via theheat sink and is dissipated from the exterior of the enclosure, whereinthe heat sink comprises a lower portion that is disposed in the secondvolume, the lower portion having a bottom surface that is in thermalcontact with the electronic circuitry, a first vertical portion thatextends at one end from an edge of the lower portion of the heat sink,and then alongside part of an edge of the substantially planar portionof the air plenum piece, a first upper portion disposed at another endof the first vertical portion, a second vertical portion that extends atone end from an opposing edge of the lower portion of the heat sink, andthen alongside part of an opposing edge of the substantially planarportion of the air plenum piece, and a second upper portion disposed atanother end of the second vertical portion, the first upper portion andthe second upper portion each in thermal contact with the enclosure sothat when the fan does not operate, heat is drawn from the electroniccircuitry to the enclosure via the heat sink and is dissipated into theexterior of the enclosure, wherein the substantially planar portion ofthe air plenum piece further comprises a central region having a smallerwidth than end regions of the substantially planar portion, the firstvertical portion of the heat sink extends alongside an edge of thecentral region, the second vertical portion of the heat sink extendsalongside an opposing edge of the central region.
 5. An apparatus forcooling electronic circuitry, the apparatus comprising: an enclosureconfigured to surround the electronic circuitry, the enclosureincluding: a first portion configured to support a circuit board havingthe electronic circuitry and having a first surface, a second portionhaving a second surface disposed opposite the first surface, and aplurality of side surfaces disposed between the first surface and thesecond surface, wherein a plurality of air intake holes are disposed inat least the second surface, and a plurality of air exhaust holes aredisposed in at least one of the plurality of side surfaces; an airplenum piece that includes a substantially planar portion that isdisposed between the first and second surfaces, the substantially planarportion being configured to divide an interior region of the enclosureinto a first volume into which the plurality of air intake holes openand a second volume into which the plurality of air exhaust holes open,and having an air plenum hole that forms an opening between the firstvolume and the second volume, the substantially planar portion having acentral region that has a smaller width than end regions of thesubstantially planar portion; a heat sink having a lower portion that isdisposed in the second volume between the circuit board and the airplenum piece, the lower portion having a bottom surface that is inthermal contact with the electronic circuitry and having a top surface,and a fan disposed atop the heat sink and in coaxial alignment with theair plenum hole such that when the fan operates, cooling air is drawnfrom an exterior of the enclosure through the plurality of air intakeholes into the first volume, then from the first volume into the secondvolume, and thereafter from the second volume through the plurality ofair exhaust holes into the exterior of the enclosure in a directionother than from a direction from which the cooling air is drawn, themovement of the cooling air in the second volume drawing heat away fromthe heat sink; the heat sink having at least one vertical portion thatextends at one end from the lower portion of the heat sink, and thenalongside at least one edge of the central region of the substantiallyplanar portion of the air plenum piece, and the heat sink having atleast one upper portion disposed at another end of the at least onevertical portion, the at least one upper portion being in thermalcontact with the enclosure so that when the fan does not operate, heatis drawn from the electronic circuitry to the enclosure via the heatsink and is dissipated into the exterior of the enclosure.
 6. Theapparatus of claim 5, wherein the heat sink comprises a first verticalportion that extends at one end from an edge of the lower portion of theheat sink, and then alongside an edge of the central region of thesubstantially planar portion of the air plenum piece, a first upperportion disposed at another end of the first vertical portion, a secondvertical portion that extends at one end from an opposing edge of thelower portion of the heat sink, and then alongside an opposing edge ofthe central region of the substantially planar portion of the air plenumpiece e, and a second upper portion disposed at another end of thesecond vertical portion, the first upper portion and the second upperportion are each in thermal contact with the enclosure so that when thefan does not operate, heat is drawn from the electronic circuitry to theenclosure via the heat sink and is dissipated into the exterior of theenclosure.